Nonoverfill and vent construction for storage batteries



' Sept. 28, 1943.

NON-OVERFILL AND VENT CONSTRUCTION FOR STORAGE BATTERIES llhhll G. S. BILES FiTed Sept. 20. 1941 Patented Sept. 28, 1943 natte NONOWERITILQ AND VENT CONSTRUCTION FOR STORAGE BATTERIES George S. Biles, Hamburg, Pa., assigner to Price Battery Corporation, Hamburg, Pa., a corpora.- i

tion of Pennsylvania nppiicationseptember 2o, 1941,seria1No. 411,606

` 4 claims. (o1. 13e- 178) The present invention relates to batteries containing liquid electrolyte,.`such as for Vexample lead. storage batteries, and it relates `more particularly to certain new and useful `closures for the vent and filling openings in the covers of batteries. y

An object of the present invention is. to provide a simple, inexpensive durable and 'dependable closure for storage batteries whereby overllling of the electrolyte-containing chamber will be prevented thereby to eliminate loss of electroly'te and corrosionI of the outside terminals and connections. Another object of the present invention is to provide a closure which will permit venting of the electrolyte-*containing chamber when said closure is inA the closed position and which will prevent overfilling of said electrolytecontaining chamberwhen said closure is opened.

Other objects and purposes of the present invention will be apparent in the `following specication and appended claims and in the accompanying drawing.

For the purpose of illustrating the invention there is shown in the accompanying drawing one form thereof which is at present preferred,4

since the same has been found in practice to give satisfactory and reliable results, although it is to be understood that the Various instrumentalities of which the inventionconsists can be variously arranged and organized-and .that the invention is .notlimited .to the precise .s arrangements and organizations of the .instrumentalities as herein shown and described. y,

Referring to the drawing in which like reference characters indicate like parts throughout: I

Figure 1 represents aQview partly in section and partly in perspective of one embodiment of the present invention as it appears when disassembled. s s

Figure 2 represents a fragmentary cross-sectional view of the embodiment shown in Figure 1 as it appears duringl a lling operation.

Figure 3 represents a fragmentary cross-sectional view similar to that of Figure '2' showing the battery as it appears after it has been lled and after the cap has been applied. Y

Figure 4 represents a planviewofavent and filling'opening embodying the present invention as it appears with the cap and the sealing washer removed. y

Figure 5 represents a plan view similar to Figure 4 as it appears when the sealing washer is in its closed filling position.

Figure 6 represents a plan view similar to Figvure 5 but showing the sealing washer in its opened venting position.

Figure 7 represents a perspective view on a reduced scale of a battery cell equipped with the present invention; Y s

According to one embodiment of the present invention, `I may provide a top cover I0 for a storage battery II. While, in the accompanying drawings, saidtop cover I0. is shown as being fitted to a single cell ,of the usual three-cell storage battery, Vitis understood and intended 'that said cover` I0 can be formed `equally well for any number of cells without departing from the spirit of the present invention. *Y `The top cover IU. may kbe'formed of hard rubber, or Bakelite or other durable and acid-resistant material and is preferably formed as an integral .junitby molding or pressing or-other similarshaping operations.

Inthe top cover ID, I mayprovide an upwardly-extending Vsocket I3 which is `internally I threaded as at I4 detachablytofreceive an exterhorizontal annular shoulder I5 peripheral to a central filling opening I6;

4nally threaded plug cap. as will be hereinafter described. k

Within said socket "I3 I provide a Agenerally Directlybeneath Ysaid annular shoulder l5 and `preferably 'an integral part thereof, I may provide` a downwardly-projecting level-determining tube I1. VVThe wallsof said tube I1 have a rela- `within the battery cella predetermined distance corresponding to the desired level of fluid within the'cell. f y

A vent opening 20 is formed in the shoulder I5 radially outward of the outer periphery of theV tube I1; saidopening 20 thereby providing communication between the socket I3 and the upper portion 2I of the electrolyte-containing chamber.

An upwardly-extending stop 2`2 is formed at the outer periphery of the shoulder I5 generally adjacent to and counter-clockwise ofthe vent vopening 20.A

A valve 23 is seated upon the shoulder `l5 and is adapted to be rotated thereupon. Said valve 23 is preferably of lead `or relatively hard lead alloy such as antiinonial lead, or of other suitable material not attacked by the electrolyte.

A valve 23 has a generally circular outer periphery corresponding to the outer periphery of the shoulder I5. A recess 24 extends circumferentially about the outer periphery of said valve 23r for somewhat less than half the circumference thereof. The recess 24 has a s'uicient radial dimension to uncover the vent opening when the valve 23 is rotated to bring the recess" 24 adjacent to the opening 20. l A central opening 25 is formed in said valve 23; said opening 25 having a generally circular wall 26 and a relatively smaller flat"wall- 2I^ preferably diametrically opposite theA recess" 2'4.

An externally threaded washer 28 is screwthreadedly engaged within the socket' I3 directly above the valve 23, thereby to prevent removalof said valve 23 from the socket I3 While permitting rotation of said valve 23 upon the shoulder I5.

A cap 29 whichv is externally screw-threaded/ as at 30 is adapted to be screwLthre'adedly secured Within the socket I3.

A central camming member or key 3|4 extends downwardly from said cap' 2'9`. member has a irusto-conial lower portion 32 of which a portion isA out away along a vertical plane to provide' one iiat vertical side 33 on said frustoLconical portion.` The iiatted frustocom'- cal portion is adapted t t Within the central opening 25Y of the valve ,23 with the iiat side 33 keying with the flat wall 2 1. I A

` The 'threads I4 and 30 are so formed that the cap 29 will seat itself firmly Within the' socket I3 in somewhat less than a half turn. -The threads i4 andl 3U are preferably square-cut toins'u're a firngrip of thecap 29,Y within the socket I3,

VThe vopening 25 in the valve 2 3A and the atted frusto-conical portion 32 of the` camming mem'- be'r3`l are so related t keach other that the' portion .32 cannot entersad openingj- 25 toany appreciable 4extent unless the flat sideA and the -flat Wall 2T are in registration. When ths'e walls are not in registration, the ,capv29 cannot fitted within the' socket ISsiCently t' permit interengagement of the threads iI4 and'.3 9,` It can beuseen that a clockwise tation of thetap 29 thethreads I4 and 30 being conventional rightlrand ,th'reads) Awill produce no resultuntil the atj'side 33 comes' in ,re`gistratio with the flat wall ,2l of the valve 23 at rys'fhich time thefrustoconical portion 32 moves' 4d'owrn'lrardly within ,the @Bening 25 thereby pefmttflg the tlfe'fs 3U 0f trie cap 29 td Aengage with the threads I4 of the socket I3 whereupona furtherfnoveme'nt of ap"- proximately one-half tturn will seat the cap 29 firmlywithinthev socketl. y

7 If the valve l2 3 isin the closedpo'sitioi -'shown in Figure' 5 ,when vthe capl is removed, ii'ser'ti'n of the par) Win anse die frusta-'esami portieri 32 to enter the opening' 25 arid to' key therewith so that the half turn during which the threads I4 engage with the threads 30, causes a corresponding rotation of the valve 23 to the open po.-

ure 5a right-hand rotation rof the cap 29 will necessarily cause a rotation of the valve until the` portion 32 and the opening 25 are keyed together at which time the valve 23 is necessarily Aturned to the position shown in Figure 5 before the threads 30 of the cap 29 are engaged with the threads I4 on thesoc'ketl3. ,l

provided in the top of the cap A Vent hole 34 is Saidcamming l 29 preferably diametrically opposed to the Vent opening 20 in the shoulder I5.

When the cap 29 and the Valve 23 are in the closed operating position shown in Figure 3, the upper portion 2l of the electrolyte-containing chamber is vented to the atmosphere through the openings 29 and 34 to permit the escape oi gases generated during operation of the battery.

One or more upwardly-extending grooves 35 may be formed on the frusto-conical portion 32 to provide additional vent openings intermediate said portion 32 and the circular wall 26 of the central opening 25 of the valve 23. The stop 22 limits the'mvement of the valve 23 to its open f or Closed position. However, as shown in Figure 6,'- I- prefe'rto position the stop 22 so that the cap 29 Will be fully engaged and the vent opening' 20 will be fully unsealed before the counterclockwise end of the recess 24 contacts the stop 22. In this way, it is impossible to apply any shearing force to the stop 22 during tightening of the'cap 29 as might break off said stop 22.

When the cap 29 is unscrewed the first rotation of somewhat less than half a turn will cause the valve 23 (which is keyed to the cap 29) to be turned counter-clockwise until the clockwise end of the recess 24 contacts the stop 22. When this occurs, any additional counter-clockwise rotation of the cap 29 will cause the frusto-conical portion 32 yto move upward and outward from the opening 25 of the valve 23; the trailing edge cf the at side 33 exerting an upward camming force on the cap 29. Such additional rotation, therefore, serves merely to li`t the cap 29 out of the socket I3; the valve 23 being held against upward displacement by the Washer 28.

A's hereinabove described, when the cap 29 is inserted within the socket I3, the valve 23 is in its open position in which venting of the upper portion 2|` of the electrolyte-containing charnler is accomplished through the openings 23 and When the c ap is unscrewed, the valve 23 is turned to its Closed position in which it seals the vent opening 2D and produces an air-lock within the upper portion 2! of the electrolyte-containing hamb'er.

is well known, the operationof a storage battery, such as for example a lead storage battery containing a sulfuric acid solution as the electrolyte, results in theV loss of Water due to evaporation andv due to the fact that water, in the @form of a re spray, is carried o by the gasesliberated during operation of the battery. Consequently, it is necessary to replace the water thus lcstirom time to time.

Itis highlyl desirable that, during such lling operation, the cells be not over-filled since, if this happens, the level of electrolyte will be too highvwithin the chamber and electrolyte will be sprayed outl during operation causing not only loss of electrolyte but also corrosion of the batteryterrninals and connecting cables as well as o r any additional electrical wiring or apparatus inthe vicinity.

The present Yinvention provides means for preventingsuch over-nllirig as will be apparent from the following description.

Assuming that the level of electrolyte 33 has, due to evaporation. dropped to the upper edges of the battery plates 37 as shown in Figure l so that the' cell requires the addition of distilled water the cap 29 is iinscrewed so that the valve 23 Which Wasin its open venting position during normal operation' of the battery, is new turned to its closed position inwhich the vent opening. 29 is sealed to create `an air-lock within the upper portion 2I of the electrolyte-containing chamber. Distilled water is then added by means of a tube or other pouring means through the central opening 25 of the valve 23 and the lling opening I9 as indicated particularly vin Figure 2. As the water is added,` the level of electrolyte 36 gradually rises until it reaches thelower edge. I8 of the level-determining vtube I'I. The addition of more `water now causes the liquidlevel to rise only within the tube I'I since the air-lock existing within the upper portion 2Iwof` the chamber prevents the rise of liquidztherein.

The person adding the water ceases such addition when he observes the liquid level rising within the filling opening I6.` Should he` fail to stop in time, any overflowwilll be practically pure water since there will be little `or 'n0 diffusion or mixing of the waterxwiththe main part of the electrolyte withinthe lsmall filling opening I6. Thus, ysuch overow will not be corrosivey to the outside terminals and will notcause any loss of. electrolyte.

After the` required ,amountof water has been added, the cap 29 is then screwedrin to force the valve 23 to its open position inwhich it unseals thevent opening 29 and breaks the air-lock existing within theiupper` portion `2| of the` electrolyte-containing chamber. When this occurs, the liquid levels become'v equalized; the electrolyte 36 rising slightly. above thel lower edge I8 of the tube I1 while the liquidilevel within the filling opening I6 drops` to the same final level. H

In this fashion, the final heightof theielectrolyte 39 within the cell reaches its correct and predetermined position, preferably slightly above the lower edge I8 of the tube I'I and more or less approximately one-halfY inch below the undersurface I9 of the top cover I9. Thus, sunlcient clearanceis provided beneath the undersurface I9 o-f the top cover I9 to minimize the danger of escaping electrolyte.

The location of the opening 34 of the cap 29 diametrically opposite from the.vent opening 29 tends to reduce loss ofelectrolyte in theform of spray, since the escaping gases must move upward through the vent opening 20 and around the camming member 3l before escaping through the hole 3d; the tortuous path thus followed causing condensation of much of the spray upon the contiguous surfaces. The spray thus condensed drains back into `the chamber through the vent opening 29 and through the grooves 35 on the frusto-conical portion 32.

While the battery is in use, the valve 23 is necessarily in its open venting position due to the positive interengagement of the member 3I with the valve 23 and when the cap 29 is removed the valve 23 is necessarily in its closed sealing position as the result of said positive inter-engagement.

Thus, it is apparent that my present invention aiords an extremely simple and entirely positive and dependable mechanism for venting the battery during operation and for preventing overfilling of the cell.

While I have shown one illustrative form of engagement between the cap 29 and the valve 23, many other forms of keying between said cap 29 and said valve 23 are possible. In its broad aspects, my present inventionis directed to any means for providing a positive engagement of the iciA cap within the'iilling opening of the rotating valve. A Y

The present invention may be embodied in other specific forms without departing from the spiritv or 4essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the ap- .face and having an opening extending from said upper seatingsurface to a point in the uppermost portionof the cell and above the lower end of said tubular skirt membeigia disc-like valve rotatably mounted upon'and disposed wholly above said seating member and having a non-circular filling opening therein communicating with said tubular skirt member, said valve having a passageway adapted to Abe brought into registration vwith the opening in said seating member to permit venting cisaid cell andto be brought out of registration with the opening in said seating member to provide an overfill-preventing air- `lock in the upper portion of` said cell above the lower end of said tubular projection, a stop for limiting the rotation of i said valve to its open venting position and its closed overll-preventing yposition respectively, andan externally threaded cap adaptedto be engaged within .said cylindrical opening and having a portion thereof generally complementary to and adapted to fit within and to key with the non-circular lling opening of said valve thereby to turn said valve toits open venting position when said capis engaged and to turn said valve to its closed overflll-preventing position when said cap is disengaged.

2. A cell cover assembly for storage batteries or the like containing electrolyte, comprising a cell cover provided with an internally threaded generally cylindrical opening, a downwardlyextending level-determining tubular skirt member, a peripheral seating member at the uppermost portion of said tubular projection, said seating member having an upper plane seating surface and having an opening extending from said upper seating surface to a point in the uppermost portion of the cell and above the lower end of said tubular skirt member, a valve rotatably mounted upon said seating member and having a non-circular filling opening therein communicating with said tubular skirt member, said valve .having a peripheral recess therein adapted to be brought into registration with the opening in said seating member to permit venting of said cell and to be brought out of registration with the opening in said seating member to provide an overll-preventing air-lock in the upper portion of said cell above the lower end of said tubular projection, a stop formed on said upper seating surface extending within said recess and limiting the rotation of said valve to its open venting position and its closed overfill-preventing position respectively, and an externally threaded cap adapted to be engaged within said cylindrical r or4 the like containing electrolyte, comprising a `cell cover provided-with an internally threaded generally cylindrical opening,

a downwardlyextending level-determining tubular skirt member, afperipheral seating member at the uppermost portion of said tubular projection, said seating member h'aving an upper plane seating surface and having an opening extending from said upper seating surface to a point in the uppermost portion of the cell and above the lower end of said tubularV skirt member, a valve rotatably mounted upon ksaid seating member and having a non-circular filling opening therein communicating with said tubular skirt member, saidv Valvehaving a. peripheral recess therein adapted to be brought into registrationwith the opening in said seating member to permit venting of said cell and to be brought out of registration with the opening in said seating member to provide an overll-preventing air-lock in the upper portion of said cell above'the lower end of said tubular projection, a stop formed on said upper seating surface extending within saidA recess and limiting the rotation of said valve to its open venting position and its closed overllpreventing position respectively, an annular washer screw-threadedly engaged within said socket above said valve and preventing Vertical displacementv of said valve, and anexternally threaded cap adapted to be engaged within said cylindrical opening and having a portion thereof generally complementary to and adapted to t .or the like, comprising a cell cover provided with a generally cylindrical Ventvand filling opening, a tubular projection extending downwardly from said opening below` said cover, a peripheral seating member at the uppermost portion of said downward projection, said seating member having an upper plane seating surface and having an opening extending from said upper seating sui"- ace to the upper portion of said battery at a poi t above the lower edge oi said downward proie tion,adisolike valve rotatably seated upon said seating member and havingA an opening therein communicating with said tubular projection, said lastementione'd opening being dened by a generally circular Wall and by `a plane wall forming a chord to said circular wall, .said valve having a. passage adapted to be brought into or out of registration with the opening .in said seating member, a vented cap adapted to be detachably engaged within said mst-mentioned filling opening,` a downwardly-extending portion of said cap having a crossfsecti'onal configuration corresponding to the coniiguration` of the lling opening of said valve and being adapted to key within the iilling opening of said valve, thereby to rotate said valve to its open venting position unsealing the opening in said seating member when said cap is engaged within said socket, and to rotate said valve to its closed position sealing the opening in said seating member when said cap is disengaged'.

GEORGE S. BILES. 

